Table 1 Primers used in this study

M isoforms primers

 1F (1–11)

5′-GGGGGAGCAAAAGCAG-3′

 2F (26–45)

5′-ATGAGTCTTCTAACCGAGGT-3′

 3F (819–839)

5′-TTGCACTTGATATTGTGGATT-3′

 1R (891–912)

5′-CTTCCGTAGAAGGCCCTCTTTT-3′

Quantitative PCR primers

 M1-F

5′-CCTCAAAGCCGAGATCGC-3′

 M1-R

5′-GGGCACGGTGAGCGTGAA-3′

 M2-F

5′-GAGGTCGAAACGCCTATCAGAA-3′

 ACTB-F

5′-GCTCGTCGTCGACAACGGCTC-3′

 ACTB-R

5′-CAAACATGATCCTGGGTCATCTTCTC-3′

The primers designed for mutagenesis

 H1N1 C55T-F

5′-CCGAGGTCGAAACGTATGTTCTCTCTATCGTCC-3′

 H1N1 C55T-R

5′-GGACGATAGAGAGAACATACGTTTCGACCTCGG-3′

 H3N2 T55C-F

5′-CCGAGGTCGAAACGTACGTTCTCTCTATCGTCC-3′

 H3N2 T55C-R

5′-GGACGATAGAGAGAACGTACGTTTCGACCTCGG-3′

 H1N1 G740A-F

5′-TCTTGAAAATTTGCAGACCTATCAGAAACGAATGGG-3′

 H1N1 G740A-R

5′-CCCATTCGTTTCTGATAGGTCTGCAAATTTTCAAGA-3′

 H3N2 A740G-F

5′-TCTTGAAAATTTGCAGGCCTATCAGAAACGAATGGG-3′

 H3N2 A740G-R

5′-CCCATTCGTTTCTGATAGGCCTGCAAATTTTCAAGA-3′